create table WORKER_NODE
(
  ID           NUMBER(32),
  HOST_NAME    VARCHAR2(64),
  PORT         VARCHAR2(64),
  TYPE         NUMBER(11),
  LAUNCH_DATE  DATE,
  GMT_MODIFIED TIMESTAMP(6),
  GMT_CREATE   TIMESTAMP(6)
);

create or replace trigger WORKER_NODE_TRIGGER
before insert on WORKER_NODE  /*触发条件：当向表dectuser执行插入操作时触发此触发器*/
 for each row     /*对每一行都检测是否触发*/
begin   /*触发器开始*/
select  WORKER_NODE_SEQ.nextval into :new.ID from dual;
/*触发器主题内容，即触发后执行的动作，在此是取得序列WORKER_NODE_SEQ的下一个值插入到表WORKER_NODE中的id字段中*/
end;